1. Field of the Invention
The present invention relates to computerized systems and methods for information storage and retrieval, and more particularly the present invention relates to a computerized system and method for the compact storage and rapid retrieval and manipulation of data that is classified and stored in the form of hierarchal information trees.
2. The Prior Art
Computerized information storage and retrieval systems have long been used to help keep track of materials and parts used at large manufacturing facilities. For example, some aircraft manufacturing companies may have as many as a half a million active parts in their inventory at any given time. Many of the parts used by aircraft manufacturing companies or other large manufacturing facilities are made by the companies themselves from raw materials which are kept on hand.
One of the major problems which these types of large manufacturing facilities have experienced in the past is the problem of how to insure that the manafacturing process for the same or similar parts is both uniform and as efficient as possible. Inefficient routing of a part from one work station to another work station may give rise to additional time and expense in manufacturing the part. Furthermore, failure to follow the same manufacturing process for subsequent parts which are the same or similar to parts previously manufactured further contributes to wasted time and inefficiency in making the parts.
Prior attempts to achieve uniformity and standardization in the process plans used by large manufacturing facilities have relied upon the development of generic process plans for certain part families. Under this type of system, the various parts which are made and stored are first classified into part families. For each part family, a generic process plan is then developed. When it is desired to produce a particular part, the appropriate generic process plan is retrieved and the process planner then modifies the generic plan to meet the requirements of the particular part which is to be made.
Although this system has helped to reduce the nonuniformity and has helped to eliminate some of the waste involved in manufacturing plants which must make a wide variety of parts, it will nevertheless be appreciated that much nonuniformity and inefficiency is still inherent in the system because each generic plan must be modified to meet the particular needs of each part that is to be made. Furthermore, since typically many process planners are employed, inconsistencies further develop because one process planner may not modify the generic plan in the same way as a more experienced process planner might.
It can thus readily be appreciated that it would be highly desirable to be able to provide a computerized information storage and retrieval system capable of quickly generating, storing and accessing individualized process plans for each of the parts manufactured at a large manufacturing facility. Unfortunately, present computerized information storage and retrieval systems are not efficient enough to be able to economically provide this capability.
The efficiency of computerized information storage and retrieval systems is a function of how compactly the data may be stored and how quickly the data may be retrieved, separated, compared and interrelated.
Prior art information storage and retrieval systems have relied upon the use of lists to access and manipulate computerized data. These lists are generated by searching through the data base for classes of data corresponding to a selected attribute. In this manner, several long lists of data may be generated, each list of data corresponding to a particular attribute. Since some classes of data may correspond to more than one attribute, data is often redundantly stored in several lists.
In order to then separate or combine that data which corresponds to a given combination of attributes, it is necessary to compare each item in one list with each of the items in the other lists. As can be appreciated, searching through a large data base, generation of long lists and the individual comparison item by item between these lists is disadvantageous in that it results in redundant storage of information, long retrieval times and difficult manipulation of data that is retrieved. This is particularly true where the generated lists require storage on secondary storage devices such as magnetic disks, which are mechanically slow and difficult to operate.
Other prior art systems for information storage and retrieval have attempted to eliminate some of the foregoing problems by using lists and pointers. In this type of system, each item in the generated list is provided with an encoded instruction which points to the location of the next item whether it is in the same or an adjacent list. Although this may somewhat help to eliminate redundant storage of information, retrieval time and manipulation of the retrieved data is nevertheless long and relatively difficult.
Accordingly, what is needed is a computerized information storage and retrieval system capable of more efficiently storing, retrieving, separating or otherwise interrelating large bodies of data. Such an invention is described and claimed herein.